I cannot speak to constitutional law, but I can speak to grammar and sentence structure, which anyone should acknowledge was probably more intimately studied and practiced in the 18th century than it is today.
The document that we call The Constitution was constructed on sets of conditional clauses, reasons and explanations. The preamble, the thesis statement if you will, is the sentence that sets the grounds for everything that follows: "We the People of the United States (the who part of the statement), in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defense, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity (the why part of the statement), do ordain and establish this Constitution for the United States of America (the what part of the statement)."
That would mean that everything that follows MUST support the WHY part of the statement. Then we skip to the second amendment, which so many like to flaunt and debate. It in itself is another conditional statement: "A well regulated Militia, being necessary to the security of a free State (the why part of the statement), the right of the people to keep and bear Arms, shall not be infringed (the what part of the statement)."
The second part of the statement cannot stand without the first, and the first does not state, in order to ensure personal safety, in order to hunt or in order to shoot 20 defenseless first-graders.
- Kim Ferraro, Crown Point